DS2155LB Maxim Integrated, DS2155LB Datasheet - Page 150

• Manufacturer Part Number: DS2155LB
• Description: Network Controller & Processor ICs
• Manufacturer: Maxim Integrated

Register Name:
Register Description:
Register Address:
Bit #
Name
Default
Bit 0/Custom Line Driver Select (CLDS). Setting this bit to a 1 redefines the operation of the transmit line
driver. When this bit is set to a 1 and LIC1.5 = LIC1.6 = LIC1.7 = 0, the device generates a square wave at the
TTIP and TRING outputs instead of a normal waveform. When this bit is set to a 1 and LIC1.5 = LIC1.6 = LIC1.7
≠ 0, the device forces TTIP and TRING outputs to become open-drain drivers instead of their normal push-pull
operation. This bit should be set to 0 for normal operation of the device.
Bit 1/Short-Circuit Limit Disable (ETS = 1) (SCLD). Controls the 50mA (RMS) current limiter.
Bit 2/Unused, must be set to 0 for proper operation
Bit 3/Jitter Attenuator Mux (JAMUX). Controls the source for JACLK.
Bit 4/Transmit Unframed All Ones (TUA1). The polarity of this bit is set such that the device transmits an all-
ones pattern on power-up or device reset. This bit must be set to a 1 to allow the device to transmit data. The
transmission of this data pattern is always timed off of the JACLK.
Bit 5/Insert BPV (IBPV). A 0-to-1 transition on this bit causes a single BPV to be inserted into the transmit data
stream. Once this bit has been toggled from a 0 to a 1, the device waits for the next occurrence of three consecutive
1s to insert the BPV. This bit must be cleared and set again for a subsequent error to be inserted.
Bit 6/Line Interface Reset (LIRST). Setting this bit from a 0 to a 1 initiates an internal reset that resets the clock
recovery state machine and recenters the jitter attenuator. Normally this bit is only toggled on power-up. Must be
cleared and set again for a subsequent reset.
Bit 7/E1/T1 Select (ETS)
0 = enable 50mA current limiter
1 = disable 50mA current limiter
0 = JACLK sourced from MCLK (2.048MHz or 1.544MHz at MCLK)
1 = JACLK sourced from internal PLL (2.048MHz at MCLK)
0 = transmit all ones at TTIP and TRING
1 = transmit data normally
0 = T1 mode selected
1 = E1 mode selected
ETS
7
0
LIRST
LIC2
Line Interface Control 2
79h
6
0
IBPV
5
0
TUA1
4
0
150 of 238
JAMUX
3
0
—
2
0
SCLD
1
0
CLDS
0
0